<?php
if(!defined('IN_MITU')) {
	exit('Access Denied');
}

class mysql_db {
	var $querynum = 0;
	var $link;
	var $charset;
	var $errnum = 0;
	var $dbhost ,$dbuser , $dbpw , $dbname , $pconnect = '';
	var $printerror=0;
	var $errorpage='';
	function connect($dbhost, $dbuser, $dbpw, $dbname = '', $pconnect = 0, $halt = TRUE, $displayerror = false) {
        $this->printerror = $displayerror;
		$this->dbhost = $dbhost;
		$this->dbuser = $dbuser;
		$this->dbpw = $dbpw;
		$this->dbname = $dbname;
		$this->pconnect = $pconnect;
		if($pconnect) {
			if(!$this->link = @mysql_pconnect($dbhost, $dbuser, $dbpw)) {
				$halt && $this->halt('Can not connect to MySQL server');
			}
		} else {
			if(!$this->link = @mysql_connect($dbhost, $dbuser, $dbpw)) {
				$halt && $this->halt('Can not connect to MySQL server');
			}
		}

		if($this->version() > '4.1') {
			if($this->charset) {
				@mysql_query("SET character_set_connection=$this->charset, character_set_results=$this->charset, character_set_client=binary", $this->link);
			}
			if($this->version() > '5.0.1') {
				@mysql_query("SET sql_mode=''", $this->link);
			}
		}
		if($dbname) {
			@mysql_select_db($dbname, $this->link);
		}
	}
	
	function ping(){
		if(!mysql_ping($this->link) && $this -> errnum < 3){
			mysql_close($this->link);//注意：一定要先执行数据库关闭，这是关键
			sleep(1);
			$this->connect($this->dbhost,$this->dbuser,$this->dbpw,$this->dbname,$this->pconnect, true, $this->printerror);
			$this -> errnum +=1;
		}
	}

	function select_db($dbname) {
		return mysql_select_db($dbname, $this->link);
	}

	function fetch_array($query, $result_type = MYSQL_ASSOC) {
		return mysql_fetch_array($query, $result_type);
	}

	function query($sql, $type = '') {

		$func = $type == 'UNBUFFERED' && @function_exists('mysql_unbuffered_query') ?
			'mysql_unbuffered_query' : 'mysql_query';
     if(!($query = $func($sql, $this->link)) && $type != 'SILENT') {
              $this->close();
              sleep(1);
              $this->connect($this->dbhost,$this->dbuser,$this->dbpw,$this->dbname,$this->pconnect, true, $this->printerror);

              if(!($query = $func($sql, $this->link)) && $type != 'SILENT') {
                      $this->halt('MySQL Query Error', $sql);
              }
      }

		$this->querynum++;
		return $query;
	}
//取lastid不能重连，会出问题
	function query_noautoconnect($sql, $type = '') {
		$func = $type == 'UNBUFFERED' && @function_exists('mysql_unbuffered_query') ?
			'mysql_unbuffered_query' : 'mysql_query';
        if(!($query = $func($sql, $this->link)) && $type != 'SILENT') {
                      $this->halt('MySQL Query Error', $sql);
              }

		$this->querynum++;
		return $query;
	}

	function affected_rows() {
		return mysql_affected_rows($this->link);
	}

	function error() {
		return (($this->link) ? mysql_error($this->link) : mysql_error());
	}

	function errno() {
		return intval(($this->link) ? mysql_errno($this->link) : mysql_errno());
	}

	function result($query, $row) {
		$query = @mysql_result($query, $row);
		return $query;
	}

	function num_rows($query) {
		$query = mysql_num_rows($query);
		return $query;
	}

	function num_fields($query) {
		return mysql_num_fields($query);
	}

	function free_result($query) {
		return mysql_free_result($query);
	}

	function insert_id() {
		return ($id = mysql_insert_id($this->link)) >= 0 ? $id : $this->result($this->query_noautoconnect("SELECT last_insert_id()"), 0);
	}

	function fetch_row($query) {
		$query = mysql_fetch_row($query);
		return $query;
	}
	
	function fetch_fields($query) {
		return mysql_fetch_field($query);
	}
	function result_first($sql) {
		$query = $this->query($sql);
		return $this->result($query, 0);
	}
	function version() {
		return mysql_get_server_info($this->link);
	}

	function close() {
		return mysql_close($this->link);
	}

	function halt($message = '', $sql = '') {
		$dberror = $this->error();
		$dberrno = $this->errno();
		if($this->printerror)
		{
			echo "<div style=\"position:absolute;font-size:11px;font-family:verdana,arial;background:#EBEBEB;padding:0.5em;\">
			<b>System Error</b><br>
			<b>$dberror</b>: $sql
			</div>";
		}
		else
		{
			if(!empty($this->errorpage))
			{
				header("Location:".$this->errorpage);
				exit;
			}	
		}	
		exit();
	}

}

?>